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When will a diesel be available for my aircraft? |
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News, facts, and comments on the coming revolution for piston-engine aircraft.In 1998, one diesel engine flew on a converted airplane for the first time since 1945. Today, close to 4,000 singles and twins are flying. This is the beginning of a worldwide trend which will eventually allow a rebirth of the piston-engined aircraft, around new specs and new missions. DieselAir Research, Inc., the publisher of The DieselAir Newsletter, offers strategic intelligence services to the aircraft industry, its suppliers and its customers who ambition to benefit from this global change of paradigm which will mean new markets, new concepts, new services, new materials and components… You may be interested in our services if your firm designs and/or manufactures aircraft and components, aero engines, avionics, propellers and engine components, fuel systems or additives, advanced materials, or industry specific machinery for manufacturing of these; or provides aviation services such as fuel production or distribution; flight training, aircraft chartering, maintenance and operations (FBO’s); or airport management and design, traffic control, hangar, materials handling and storage equipment; or consulting and financial services for these industries; or advertising, sales promotion, trade shows, specialized publications. To know more, send a confidential email inquiry to Dr. Eng. André Teissier-duCros at atc@geanoverseas.com News of November 22, 2005Diesel Saga 3: How the French IRS unintentionally came to help diesel technology in Europe.France was with Italy a pioneer of high gasoline taxes. When it comes to taxes, never underestimate French know how which has lead the world for several centuries! After World War II, the country’s economy was ruined and running a tremendous trade deficit. A severe protectionist policy was enforced, which lasted until the 1957 Rome Treaty establishing the Common Market and then gradually faded out within 11 years. Petroleum products being imported, motor gasoline was taxed sky high. But this was hurting the trucking business, which lobbied to obtain much lower taxes on diesel fuel. From the fifties to the eighties, motor diesel was half the price of gasoline. Other countries followed the practice although not all at the same level. And immediately more taxi drivers saw the advantage of shifting to diesel and spend some 75% less per mile. In 1975-80, with my Citroen diesel used for business travel across Europe, I was making money on the standard mileage rate I was charging to my business which was based on gasoline costs. This “privilege” of diesel cars eventually was noticed by general consumers, and the smart ones started buying diesel sedans. Manufacturers saw the market opportunity and decided to work on eliminating the traditional setbacks of diesel: noise, smell, solid particles emission, weight, and low power per weight. In the seventies Peugeot broke ground with the 1,100 c.c. 204 diesel, the smallest diesel on the market. Diesel cars, within 30 years, became what they are today which amazes the American public. They are capable of 125 and even 140 mph, are as silent as a conventional car, and are even more fuel efficient than before. Female drivers love them. A small diesel car does 60 miles to the US gallon while respecting the speed limits (which are higher than in the US.) By now, European diesel technology is decades ahead from what sell as diesel in the US. It is this diesel technology which was the base of aero diesels in the hands of engine manufacturers who had the experience of high performance racing cars: Thielert in Germany; SMA in France which was the offshoot of the ex-Renault Sports engine design for Formula One cars; Wilksch in the UK which was founded by two ex-Cosworth engineers (see soon our story on Wilksch…). posted at 2:45 AM The Beech Duke Thielert conversion shows what a breakthrough diesel can makeGermany: The Beech Duke with Thielert V8 350HP has flown for the first time on November 18. This is the first diesel conversion that demonstrates a reduced weight compared with original gasoline engines: Exactly 50 Lbs. The Duke diesel is faster by 10 Knots at FL 220 despite a slightly lower power at sea level. Here is comparative performance figures claimed by Martin Hagensieker, see http://www.dukeb60.de/ with photographs: ______________Diesel V8__________________Lycoming Power_________350 hp_____________________380 hp At rpm________2.300______________________2.900 Cruisepower______70 %_______________________67 % At rpm________2.000______________________2.500 Fuelflow/h______2 x 45 ltr./11 gal._____________2 x 80 ltr./20 gal. Fuel capacity_______78 ltr./232 gal.__________878 ltr. 232 gal. Fuel___________Jet-Fuel__________________AVGAS 100 LL Fuelprice Europe___65 – 1,45 EUR/ltr._________1,45 – 1,80 EUR/ltr. Fuelprice USA____3 – 4 USD/gal._____________4 – 5 USD/gal. Speed________220 kts/FL 220______________210 kts./FL 220 Climbspeed______1,200 ft/min________________1,000 ft/min TBO__________2,400 hour__________________1,600 hour Price for Overhaul___2 x 50.000 EUR____________2 x 60.000 EUR Price for first kit___2 x 175.000 EUR__________N/A Range___________2.000 nm_________________1.100 nm Note that with a range of 2,000NM, the Duke Thielert can fly from any destination in Western Europe to any destination on the East coast of North America both ways in three legs, with required reserves on the Atlantic. And, at the (low) market price of a Beech Duke today, plus some $ 400,000 conversion cost, and a fuel flow of 22 gallons/hour of Jetfuel, it will be the most affordable business aircraft for such a mission. posted at 1:56 AM News of November 16, 2005News from Vulcanair, ItalyVulcanair manufactures the P68 range of fixed gear 200HP twins, max. weight 4,630 Lbs, useful load 1,720 Lbs., 6 seats, and is steadily selling around 10 P68C piston twins a year, or one-fifth of its maximum capacity. Director of sales Remo De Feo says sales could increase once its long-planned diesel-engined variant is in production. An improved spare-parts distribution network in its key export markets of Australia and the USA will also help sales, he adds. Such small companies face hurdles, not least at a time when all manufacturers are increasing production, placing demand on suppliers. The fear is that smaller companies come further down the pecking order when it comes to the supply of components, systems and even raw materials. Vulcanair is pushing on with development of the P68C diesel version. The sole prototype has performed 45h flying and needs a further 30h before certification. The program is using a diesel developed by French manufacturer SMA and Vulcanair is waiting for engine modifications. “We’ve taken a conservative approach on this programme; we haven’t taken any orders yet and we won’t until it is fully tested and certificated,” says De Feo. (Justin Wastnage, Genoa, 11/05) posted at 4:47 PM Diesel Saga 2: How taxi diesels in Europe demonstrated a unique advantage (1950-1980).Yes, you all know that a diesel is more fuel efficient. However, this was only one of the three reasons why taxi drivers were first to promote diesels. The two others are: more longevity combined with lower maintenance costs (otherwise taxis wouldn’t touch it); and constant specific fuel consumption. And now if you really want to understand why diesel technology will rescue General Aviation, you have to bear with me for a little bit of theory. A diesel engine falls in the very general family of combustion engines. Steam engines, gasoline engines, gas engines (using natural gas or generated gas), diesel engines, turbojets and turboprops, and ramjets, are all combustion engines. All try to convert the heat from combustion, measured in Btu s or Joules, into some kind of mechanical energy measured in Horse-Power or Watts. And they only succeed to convert some of it: their efficiency is generally much less than 50%. (Do not complain too much however; remember that you need that heat to keep warm in winter and to clear your windshield.) All these engines burn a fuel, use the heat to incite motion and pressure in a gas, and recover that pressure in a mechanical device. An external combustion engine or steam engine has an efficiency of 4 to 8% when using straight steam and up to 17% when using dry hyperheated steam. An ignition engine, using an electric spark to trigger the combustion of a compressed fuel/air mixture, achieves 24 to 28%. A diesel engine achieves well over 30% and up to 50% for very large ship engines. A turbojet working in ideal conditions (40,000 ft high, stabilized cruise), gets closer to 60%. A ramjet at supersonic speeds can in theory reach 80%. (If you don’t know what a ramjet is, contact me through our Forum). The difference in efficiency is a consequence of the Carnot Principle (yes, Carnot was French, but he was right) which says that efficiency increases with the difference of temperature between the colder temperature and the higher temperature to which the gasified fuel is exposed. Which incidentally is why your engine runs better in winter… With internal combustion, your temperature can be the one at which your fuel burns, which is much higher than steam temperature; and it will be highest if materials exposed to combustion can stand highest temperatures which is much easier with turbines, and even easier in a ramjet where all parts are static (no moving parts). A diesel ignites its fuel by compressing air at a much higher temperature than a gasoline engine, high enough for combustion to be spontaneous: No spark plug, no magnetos, higher efficiency. This is why diesel is always more fuel efficient. But wait, it gets more complicated… The beauty of the reciprocating piston engine compared to turbine or other rotary system is that, at each revolution, the piston slows down, stops at maximal compression, and then moves again. In other words, it is kind enough to wait while the combustion takes place. This is why any piston engine can deliver power at variable rpms, typically between 500 rpm and 5 to 7,000 rpm. Here both diesel and gasoline engines are at an advantage, which is why you never saw a turbine automobile… Incidentally this was why the US Navy was reluctant, until the fifties, to adopt jet aircraft for aircraft carriers: At low speeds, a turbojet cannot deliver the force a piston engine delivers instantly with full throttle and full prop. And what will happen when the pilot misses its landing and needs to put full throttle to go around? Eventually the solution was found, part of it being longer runways on bigger carriers… Here visit http://hypertextbook.com/physics/thermal/engines But now comes the hidden advantage of diesel: Not only it can deliver power at different rpms, but on top of that, because the fuel is directly injected at exactly the right temperature without waiting for the propagation of a flame within the combustion chamber, (propagation depending itself on whether each of your plugs are clean and in good condition) you always use the exact amount of fuel you need whatever the rpm. So, efficiency remains high at all rpm, even when your taxi is fighting the traffic at 5 miles an hour on Fifth Avenue. European taxi drivers were the first to discover that their Mercedes 170 or 180 machines delivered a high mileage even in city driving, which is their main occupation! And diesel taxis started gaining market share, to the great benefit of the Daimler-Benz company. You can experience the same thing with a 172 Thielert, a Diamond diesel or a 182 SMA: Reduce your speed to maneuvering speed or to best glide speed and you will observe fuel flows going down to 2.5 to 3,5 GPH instead of 6 or 8! However we needed another actor to enhance the demonstration: the French IRS. This will be my next story… posted at 4:38 PM News of November 05, 2005Diesel Saga 1 - Did you know that the Hindenburg Airship had diesel engines? Read on, it has to do with your future diesel plane.The Hindenburg had 4 Daimler-Benz 1,100 HP diesels, to carry 50 passengers plus a big crew. It was over 800 ft long, and over 140 ft diameter at its largest section. And it needed as much fuel to cross the Atlantic as a Boeing 747: kerosene, in both cases. But a 747 can carry 7 times more passengers and goes some 7 times faster. Its predecessor the Graf Zeppelin, by far the most successful airship – it made 74 return trips to Rio de Janeiro, several round the world trips with passengers, never had an accident and ended as scrap metal – had 5 diesels: 12 cyl., 570 HP Maybach. Visit http://www.allposters.com/-sp/Graf-Zeppelin-Hamburg-Amerika-1937_i421193_.htm Other aircraft using diesels were flying the German Junkers 2-stroke, Jumo 200-series with opposite pistons and double geared crankshafts, the most fuel efficient engine ever designed. Visit http://en.wikipedia.org/wiki/Junkers_Jumo_205. and http://www.enginehistory.org/Diesels/CH4.pdf They were the Dornier 18 flying boat, the Junkers 86 bomber, the Blohm & Voss Ha 139 flying boat (German equivalent of the PBY), and the superb Dornier 26 4 engine flying boat with a range of 4,400 miles, Visit: http://www.warbirdsresourcegroup.org/LRG/do26.html Engine power went from 500 to 1,000 HP. Projects were in development at the end of the war aiming at much higher powers. Why was the aero diesel concept abandoned after WW2? The most obvious reason was that it was essentially a German technology and that the German engineering teams, plus most of their blueprints, test benches and results, and labs had been captured, destroyed, or dispersed. Also both the allies and the Soviets were obsessed by taking control of what was obviously superior, and of a strategic nature, in German know how: rocket engines and their fuels, rocket missiles, possible nuclear research, turbojets, and high speed aircraft. Diesels would have been of interest for commercial airliners, but in that field the apparent superiority was American with the superb Wright and P&W radials, and to some extent British with the remarkable Bristol Hercules sleeve-valve radials. Also the Atlantic scene had changed: Before the war, there were no airfields; therefore the obsession with flying boats and airships that do not need one, and with ultra long range planes which the Germans were thinking of. After the war, airfields were in place in Gander, Goose Bay, Shannon, Reykjavik, the Azores… PanAm’s DC3s could fly across the Atlantic in three 1,500 NM legs. It was a long trip, but reliable; surplus DC3s were a dime a dozen; and gasoline was cheap… So the aero diesel engines were moved in the drawer of “wrong time, wrong specs” technology, together with airships and mega-flying boats. However, Mercedes-Benz had already developed a diesel sedan, and went on after the war, being for a long time the sole manufacturer of such diesel passenger cars. They were quickly discovered by European taxi drivers who for a long time were the sole supporters of that technology. Why? This will be my next story on the aerodiesel saga. posted at 6:33 PM First US Twin Star Delivered.Diamond s first US delivery of its exciting new DA42 Twin Star was made Friday at AOPA Expo, to Mr. Henry Van Kesteren of St. Petersburg, Florida. The aircraft was delivered by Mike Bayne of Mid Atlantic Diamond and Art Spengler of Premier Aircraft Sales. “I wanted the aircraft for its cutting edge technology,” said Mr. Van Kesteren, who has accumulated over 38,000 hours flying since joining the US Army Air Corps in 1942. “This really changes everything,” said Peter Maurer, President of Diamond Aircraft. “The Twin Star represents an absolute quantum leap, with its modern all carbon airframe, Garmin G1000 and TAE 1.7 Centurion turbo diesel engines. With twin engines, known ice certification and single lever throttles, the DA42 sets new standards with regard to safety and ease of operation.” Diamond aircraft, 11-3-05. posted at 6:29 PM |
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